Wood joining article



Patentea'Nov. so, 1931 2,100,415

UNITED STATES PATENT oFFlcE WOOD JOINmG ARTICLE Olav Trygve Theodorsen, Oslo, Norway Application May 28, 1935, Serial No. 23,956 In Germany March 30, 1935 l 3 Claims. (Cl. 85-11) The invention relates to joints for wood con- The teeth may also be bent out from theY sheet p v structions in which sheet metal plates are introwith less teeth on one side than on the opposite duced between the wooden parts, the plates beside, whereby the sheet may be used when yconing provided with teeth, bolts, screws, rivets, necting very hard wood to softer wood. nails or similar fastening means being used for The teeth may before the bending operation holding the wooden parts together. and preferably also before the slitting operation Characterizing the invention is a peculiar be exposed to a pressing operation for reducing arrangement of the teeth which enter into the the thickness of the material so that the teeth parts to be connected. According to the inmay take on the desired sharpness l0 vention the plates are formed in such a manner The invention is illustrated in the enclosed m that their borders are formed as broken lines, i. e., drawing. f' alternately teeth and recesses or notches. Each Fig. 1 shows a sheet having broken borders and tooth is bent out from the sheet between a notch slits in the projecting edges. and-the border respectively between two notches. Fig. 2 shows a sheet having the form of a reg- By producing the joining article from a blank ular star. 15 having a wavelike or zigzag shaped border angles Fig. 3 shows a starshaped sheet having waved of less than borders.

(n-z) .180 Figs. 4 and 5 show a tooth ribbon having zig- 2n zag borders forming in extended lengths which are adapted to be divided in half.

Fig.A 6 shows a sheet .having two slits in the 20 same point and three teeth converging toward one point.

Fig. '7 shows a sheet having teeth provided with greater tooth angles on one side than on the 0pposite side.

Fig. 8 shows a portion of a sheet having teeth sharpened by reduction of the thickness of the (in which n represents the number of sides of the blank) are obtained.

According to the invention sheets having desired tooth angles may be obtained and simultaneously the teeth may take up a non parallel 2 position to the direction of thev series of teeth. In this way there is obtained the advantage that the teeth may be more acute or more obtuse than 90 in accordance with the hardness of the n Wooden parts which are to be connected and simaterial "n multaneously the advantage may be obtained that orhulleorms the bendmg lmes may dlrect 3U the teeth have suitable. bearing surfaces if the direction of the force is parallel to the direction of the series of teeth. Especially is to be observed that torsion moments may also be taken up as the teeth cannot act either as a saw or as a cutting device.

The notches are arranged in the -projecting parts of the border of the sheet preferably the sheet edges so that teeth having angles less than 90 may be produced.

The borders may also be formed as zigzag lines and may be provided with two or more slits projecting from the same point in several directions, more than two teeth meeting at one point before being bent out.

The sheet may have the form of a regular polygon or a star and preferably the number of sides should be divisible by four. In this way a particularly favorable form of the plate havthe f orm, of a regular Star andhavmg slits ex' ing tooth angles less than 90 and also a favor` tendlng inwardly from the points of .the star able method of production may be Obtained Fur and bisecting the angles thereof to provide teeth,4 ther the Several teeth may on the Same Sample the angles of the teeth being less than have different angles and preferably greater an- (n-2) .180 gles on one side than on the opposite side of the 2n sheet. degrees in which n represents the nurbe of star 55 The sheets also may be circular, oval, polygonal or have any other form or may be produced in the form of extended ribbons.

The sheets may have bolt apertures or not. The sheets may be placed parallel to the wood bres, or the direction ofthe force, at a right angle or obliquely to the same. 'I'he teeth may be bent or a smaller angle out from the sheet.

The sheet may be used'in wood construction of any kind, in framed buildings, dowel beams, 40 full wall beams and the like. Two or more wooden parts may be connected. In the same sheet the teeth may have equal ordilerent heights. Preferably acute-angled teeth are produced on square, roundand oval'recessed sides.

I claim:

l. A wood joining article comprising a plate in 3. A wood Joining article comprising a regular polygon the sides of which are divisible by four.

. said plate being slit inwardly at the outer corner angles each by two slits trl-sect-ing the point angles.- the teeth being bent out from the plane of the plate alternately to either side, the number of teeth bent to one side of the plate being in excess of those bent to the other side of the plate.

OLAV TRYGVE THEODORSEN. 

